GMK (Progenics Pharmaceuticals).

Abstract

Progenics Pharmaceuticals is developing GMK vaccine (a ganglioside conjugate vaccine coupled to keyhole limpet hemocyanin and formulated with the adjuvant QS-21), licensed from the Memorial Sloan-Kettering Cancer Center, for the potential treatment of melanoma and other cancers [194258], [325284]. It was previously under co-development with Bristol-Myers Squibb, but in May 2001, all rights to the GMK vaccine were returned to Progenics [409168]. It was the first of a new class of ganglioside conjugate vaccine evaluated by Progenics [194258]. GMK vaccination induces antibodies against GM2 ganglioside capable of specifically killing melanoma cells. Melanoma patients with antibodies against GM2 ganglioside have significantly improved disease-free and overall survival compared to antibody-negative subjects. The vaccine is undergoing two phase III trials, the first comparing GMK to high-dose IFNalpha in melanoma patients with more serious disease and at a high risk of relapse, and the second, in collaboration with the European Organization for Research and Treatment of Cancer, comparing GMK (14 doses of GMK over three years) to no treatment other than close monitoring of malignant melanoma patients at immediate risk of relapse [409168]. In February 1999, Lehman Brothers predicted that the vaccine had a 50% probability of reaching market, with an estimated first launch date in 2002. The analysts predicted potential peak sales in 2008 of $150 million in the US and $100 million in the rest of the world at that time [319225]. In January 2000, Lehman Brothers expected that an NDA filing would take place in 2002, with possible launch of the vaccine in 2003. In addition, Lehman Brothers estimated potential peak sales at $500 million [357788]. In August 2000, Punk, Ziegel & Company predicted that Progenics Pharmaceuticals will become sustainably profitable in 2003 following the launch of GMK and PRO-542 in 2002 [390063]. In July 2001, Ladenburg Thalmann predicted a $257 million market potential for GMK in the US, with the non-US market equivalent to the US market. A launch date of 2005 in the US, with a worldwide launch in 2006, was estimated [433347].